Food Poisoning Health Center

FDA Narrows Spinach Warning

Q. Is this strain of E. coli more dangerous than other strains?

A. Yes.

"E. coli O157 is a particularly dangerous type of E. coli because it can lead to hemolytic uremic syndrome," a form of kidney failure, says CDC spokeswoman Christine Pearson. "So it can be more severe for people."

Q. What are the symptoms of E. coli infection?

E. coli O157:H7 causes diarrhea, often with bloody stools.

"Anybody who does develop diarrhea after consuming fresh spinach should see their doctor and also ask [the doctor] to take a specimen for testing," Pearson says.

Most healthy adults recover completely within a week, but some may develop hemolytic uremic syndrome.

Q. How long does it take for symptoms of E. coli infection to appear?

A. "Twelve to 36 hours, normally. Up to a week in some cases," Richard Linton, PhD, tells WebMD. Linton is a professor of food science and the director of the Center for Food Safety Engineering at Purdue University.

Q. What is hemolytic uremic syndrome?

Hemolytic uremic syndrome is a life-threatening complication of E. coli infection affecting the kidneys.

It's usually treated in intensive care and often requires blood transfusions and kidney dialysis. Young children and the elderly are particularly at risk for the complication.

Even with intensive care treatment, the death rate for hemolytic uremic syndrome is 3% to 5%, according to the CDC.

Q. Do most infected people develop hemolytic uremic syndrome?

A. No. An estimated 2% to 7% of infections lead to this complication, according to the CDC's web site.

Q. For people who want to try other greens, what are some alternatives?

A. If you're looking for fresh greens, try lettuces such as radicchio, escarole, and romaine. Arugula, collard greens, mustard greens, and kale are other options, say Amy Jamieson-Petonic, RD, and Lola O'Rourke, RD, spokeswomen for the American Dietetic Association.

"We don't want people to stop eating fresh fruits and vegetables, because they're so important for good health," says Jamieson-Petonic. "They're wonderful sources of vitamins and minerals."

Jamieson-Petonic manages the Fairview Hospital Wellness Center in Rocky River, Ohio, near Cleveland.

Q. Should we worry about frozen spinach, canned spinach, or spinach baby food?

A. No.

At this time, the FDA has no evidence that frozen spinach, canned spinach, or spinach in pre-made meals manufactured by food companies are affected. These products are safe to eat, according to the FDA.

"Frozen spinach is normally blanched with hot water or steamed prior to being frozen, which should be effective for destroying E. coli," Linton explains.

"The thermal process given for all low-acid foods, including baby food and canned spinach, is done at 230 [degrees Fahrenheit] or higher, where E. coli will be destroyed. E. coli is destroyed at 160-165 [degrees Fahrenheit]," Linton says.